A heart with no body; the Turbo 10hp Briggs & Stratton. Aka Timebomb.(56K beware!)

65ShelbyClone

Well-Known Member
#1
A heart with no chassis; the Turbo 10hp Briggs & Stratton. Aka Timebomb.(56K beware!)

I know mdb mentioned my project a few times, but rather than derail the "intro" thread, I thought I would showcase the whole thing here where I have the room for pictures, commentary, and feedback. You all seem to like old stuff, weird stuff, and going fast, so I'll share my old, weird, and hopefully fast engine.

I usually have time to let my mind wander and my interest in fast cars led to interest in powerful engines. Putting time + interest together, I got the idea to turbocharge a lawntractor engine. I already had the engine from a Montgomery Ward tractor and a small spare IHI turbo from a DIY turbine engine project.This was the original idea circa 2001-2002:



I wanted to squeeze every last drop of power out while spending as little as possible, so I studied some on old school flathead porting techniques and went nuts on the Briggs. I didn't have any fuel parts or plan at this point:







Oh yeah, and some DIY titanium retainers:


I wanted to be able to intercool it, so a draw-through carb setup was out. That left the options to a blow-through carb or EFI. Since they both needed nearly the same fuel system components, I decided on EFI. I and had the idea to retrofit a system from an '89-90 Nissan 240SX:



After literally weeks of intense research, it became clear the the Nissan JECS system was going to be a tuning nightmare for something this far removed from the original 2.4L engine. It can be chipped and tuned for a car just fine, but not this; I would be in uncharted territory. After several months of tinkering with and studying electronics, I broke down and bought a MegaSquirt EFI computer kit(assembly required).



I already knew my "small" IHI turbo was far too big for what I wanted to do, so I started looking for the smallest one I could afford. After a few months of searching, I scored this little Garrett GT-15(far left, IHI right):



I had to build custom flanges for everything. Luckily I was working in a machine shop at the time.


Preliminary turbo header made out of pie-cut 1" steel water pipe:


Preliminary intake manifold:


Soldered fuel rail and Nissan regulator:


Modified Ford in-tank EFI fuel pump.:


Billet aluminum turbo oil drain I hacked up over a lunch break:


Mockup:


Setup as it stood when I first started the engine:


At first startup I had a Honda XR600 carb I was using as the throttlebody. Since then I picked up a pair of EFI throttle bodies from a Suzuki street bike. The intake design has turned out to be a POS, so I'm redoing that right now.

I'll cut this a little short(?!) since it's pushing 1am here. Questions, comments, and recommendations are welcome. Hopefully I put this in the right forum.
 
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65ShelbyClone

Well-Known Member
#6
Thanks y'all. In the next two weeks or so I expect to have time to start fabricating another intake manifold. Short of a self-contained oiling system for the turbo, that's really the biggest hurdle right now. Behind those I guess would be full ignition control and rev limiter/flatshift/turbo anti-lag, which I don't have set up yet.

I really wish I still had the 16hp Briggs iron-block flathead I sold years ago(for $80 :mad2: ). It would have been great fun to intall a rod, piston, and full pressure oiling on that. :thumbsup: Heck, If I was still working in a machine shop, I could have built a billet OHV head for it, kinda like how Vogel put a Kohler 361 OHV head on one of their Jones 341 flathead blocks.

Hey MDB, I got a wild hair and started looking at fullsize drag bikes to get ideas for a frame design. I have something in mind that will be about 1/2 to 2/3 scale and most likely will have a Vaguard twin of some kind. :shifty: I want to avoid a bike engine if I can. Not really a "minibike" if it has a motorcycle engine....

EDIT: I almost forgot this...
 
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65ShelbyClone

Well-Known Member
#8
Yup. I was thinking of that picture too when I decided on a direction to go.

Might hook things up to a 4-speed transmission of I can find one that isn't priced like gold.
 

65ShelbyClone

Well-Known Member
#11
you should throw on a blow off valve on it, it would sound sick and help as well!
With my new setup I'll have to.....so yeah, a bov is on the parts list. :scooter: However, I'm going to try using the flatshift feature in my MegaSquirt and see if I can shift a sequential trans without even blipping the gas. The bov will only be used when I shut down in that case.

65,

Here is an example that is available at most Harley dealers. We are planning on a 1/2 or 1/3 scale with a Vanguard V-Twin engine.

You can buy a drag-ready V-Rod at the Harley dealer?

Doggone it! I was going to do the same thing! Well, mine will be stretched, though. It's no good if I go over backward everytime I launch on the 2-step. :cool2:

I'd actually accomplish something if I didn't keep buying other parts like more turbos.
 
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#13
let me know if you need an hks blowoff valve. Not sure if it will fit but with your skill, fabbing one up to make it fit shouldn't be a problem.
 

65ShelbyClone

Well-Known Member
#14
i didn't bikes use a 2 step...
Drag bikes do.....at least some anyway. It's the most effective way to hold the throttle wide open without overevving the engine. In my case, it has the added benefit of building boost before launch.

let me know if you need an hks blowoff valve. Not sure if it will fit but with your skill, fabbing one up to make it fit shouldn't be a problem.
I do need a bov, but I need one cheap. Let me guess, one of the HKS SSQV "Super Sequential" valves? That would be kinda large, but it would work. Maybe I'll also look for a Tial knockoff for the extra bling.
 
#15
HAHA i guess maybe a ebay knockoff would be the way to go. My previous car had the hks and i prefer the sound better than any other BOV. In any case, this will be a sweet project. good luck.
 
#17
Hey x-90...I want to apologize for all that crap I was throwing around a few months ago...insulting authentic restorers like yourself...it was really stupid of me.

I was trying to generate some interest, but I definitely went about it the wrong way. I'm truly sorry...I think I really insulted you...please accept my apology.

It won't happen again.
 

65ShelbyClone

Well-Known Member
#20
So now that we're all still friends, I did a little work today.

I took one of my big Ford fuel injectors and started modifying it to work in one of the Suzuki throttlebodies I'm going to use. If the fuel distribution is good, that means I still have the option of installing a second port injector if I somehow manage to exceed 50hp on the single squirter. If this idea doesn't work, I'll go back to plan B by using the Suzuki injector as a supplement and run a main port injector. Maybe I'll use the 'zook injector for methanol injection so I can get by without an intercooler.

I was able to cleanly remove an o-ring lip on the Ford injector nozzle with a bench grinder, but the inlet will need some lathe work to make it right. Just a matter of turning down a diameter and adding an o-ring groove.
 
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